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1.
Spectral analysis of the electroencephalogram in neonatal rats chronically treated with the NMDA antagonist MK-801. 总被引:1,自引:0,他引:1
J A Gorter M Veerman M Mirmiran N P Bos M A Corner 《Brain research. Developmental brain research》1991,64(1-2):37-41
In order to study the involvement of NMDA-receptor activation in brain development, rat pups were chronically treated with the non-competitive NMDA antagonist MK-801 during the neonatal period. We recorded the cortical EEG at various vigilance states throughout the treatment period. Spectral analysis of the EEG showed reduced power in the delta (delta) frequency range (1.5-4 Hz) during quiet sleep and less power in the theta (theta) range (4-7 Hz) during REM-sleep in MK-801 animals than in controls. No significant differences were found for the total time spent in each of the different vigilance states. We conclude that chronic MK-801 treatment probably causes a developmental retardation in state-related brain activities. 相似文献
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5.
This paper reports a study which aimed to develop an understanding of newly registered nurses' attitudes, knowledge, confidence and educational needs in relation to cancer care. An educational intervention designed to meet these nurses' needs was then developed and evaluated with 127 newly registered nurses from two general hospitals. Nurses attended two different educational interventions; one group of nurses completing a 3 day experiential workshop; and a second group attended a more formal seminar programme. A third group of nurses who were unable to obtain study leave were followed up as a control group. A triangulation strategy was used to collect data from different sources, and included a baseline study, and a study of nurses before, after and 3 months following the educational interventions. Data from the study revealed the perceived need and desire for more education on cancer care, and the strong association of cancer with death amongst newly registered nurses. Significant benefits to those nurses attending the workshop were demonstrated. These differences were however less obvious at 3 months follow-up. 相似文献
6.
We report an adult female with a rare giant choledochal cyst. The patient presented following a normal pregnancy with the classical triad of an abdominal mass associated with jaundice and right upper quadrant abdominal pain. The cyst was excised using an intramural technique and biliary reconstruction achieved with a Roux-en-Y hepaticojejunostomy. Our patient has remained well with no evidence of malignancy over a 12 year review period. The aetiology and current management of this condition are discussed. 相似文献
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8.
Na+ dependence of in vitro pancreatic amylase release 总被引:1,自引:0,他引:1
9.
Determination of optimal cryoprotectants and procedures for their addition and removal from human spermatozoa 总被引:9,自引:7,他引:9
The objective was to test the hypothesis that the optimal cryoprotective
agent for cryopreservation of human spermatozoa would be a solute for which
cells have the highest plasma membrane permeability, resulting in the least
amount of volume excursion during its addition and removal. To test this
hypothesis, theoretical simulations were performed using membrane
permeability coefficients to predict optimal procedures for the addition
and removal of a cryoprotectant. Simulations were performed using data from
four different cryoprotectants: (i) glycerol, (ii) dimethyl sulphoxide,
(iii) propylene glycol and (iv) ethylene glycol. Thermodynamic formulations
were applied to determine approaches for the addition and removal of 1 M
and 2 M final concentrations of cryoprotectant, allowing the spermatozoa to
maintain a cell volume within their osmotic tolerance limits. Based on
these data, ethylene glycol was predicted to be optimal for minimizing
volume excursions among the solutes evaluated. These predictions were then
experimentally tested using glycerol as the control cryoprotectant and
ethylene glycol as the experimental cryoprotectant. The results indicate
that there was a higher (P < 0.05) recovery of motile spermatozoa after
cryopreservation when using 1 M ethylene glycol than with 1 M glycerol,
supporting the hypothesis that use of the cryoprotectant for which the cell
has the highest permeability will result in higher cell survival.
相似文献
10.
Comparison of isolation of Haemophilus vaginalis (Corynebacterium vaginale) from peptone-starch-dextrose agar and Columbia colistin-nalidoxic acid agar. 下载免费PDF全文
A total of 447 cervical or vaginal specimens were inoculated in parallel onto peptone-starch-dextrose (PSD) and Columbia colistin (10 mg/ml)-nalidixic acid (15 mug/ml) (CNA) agar and were incubated for 48 h at 35 degrees C in an atmosphere with 2 to 10% CO2. One hundred (22.4%) of the cultures were positive for Haemophilus vaginalis. Forty-eight of the isolates were recovered from both PSD and Columbia CNA agar, five from PSD only, and 47 from Columbia CNA agar only (P less than 0.001). On Columbia CNA agar, 76 of the isolates were detected after 24 h of incubation, and the remainder were detected within 4 days of incubation. 相似文献